1. Introduction

The ancient Roman and Latin poets Tibullus and Ovid may have been the very first to describe the Italian capital city as ‘eternal’, but thousands of years of travelers since then have agreed (Mike, 2010). The stunning attractions in the current World’s 16th Most Visited City (Choong and Hedrick-Wong, 2016) include the historical 60,000 seat Colosseum (built in the 1st century AD) right alongside corporate headquarters for the global fashion brand Fendi, built 19 centuries later (Bhasin, 2015). My academic eagerness to learn more about Rome’s famous engineering and architecture was a driving impetus for my participation in ‘Engineering Rome.’ Architect, author, and explores and explains Rome’s urban sustainability in his 2015 book, “Rome Works: An Architect Explores the World's Most Resilient City” as well as his popular online blog ‘Sustainable Rome’. Ancient Roman design and construction continue to impress and inspire people around the world; in fact, it was Roman engineers who perfected the arch, the vault, and the use of concrete. Rome managed to support as many as a million simultaneous permanent residents as early as the 1st century AD: “Roman engineers and ingenuity built massive structures out of stone, wood and miraculous which still act as models for our own modern edifices.” (Museum of the City, 2017) In this paper, I will analyze an example of Roman sustainability through the Circus Maximus.

In the words of Carl Elefante “The greenest building is...one that is already built.” (Journal of the National Trust for Historic Preservation, 2007) Sustainability in modern civil engineering and infrastructure projects might include use of locally-sourced materials, or construction components that can be easily dismantled and repurposed in the future. The ancient Circus Maximus was a stadium designed for chariot racing; only pieces of that original structure survive today. Sustainable design includes vision for the project long after construction has finished. The Circus’ physical location was selected and planned to capitalize on geographical and topographical features with such enduring success that it remains a public gathering space today, despite virtually none of original circus structure remaining.

2. Definition of Sustainability and Resiliency

One of the most well-known definitions of sustainability is from the 1987 United Nations Report of the World Commission on Environment and Development: Our Common Future. This global report defines sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” (Our Common Future, 1987) Being sustainable is often considered with respect to the environment, society, and economics. (Figure 1) Sustainable practices support economic, ecological, and human health. A sustainable project presumes that resources are limited, and should be allocated wisely with long-term priorities and consequences kept in view. Sustainability is about protecting the world in which we leave future generations. Measures of a project's sustainability are answers to questions such as:
  • Is the project affordable over a long period of time?
  • How will this project impact the environment?
  • Will this project still have use and meaning in society over years?
  • How will the project respond to a natural disaster?

Figure 1
For a project to be sustainable, it must be maintainable for several generations. In context of the Circus Maximus, we will explore three aspects of its sustainability: resiliency, social, and environmental sustainability.

Resiliency is the ability to recover from stress, strain, and disaster. Economically, resiliency can be defined as “decomposed into two components: instantaneous resilience, which is the ability to limit the magnitude of the immediate loss of income for a given amount of capital losses, and dynamic resilience, which is the ability to reconstruct and recover quickly.” (Hallegatte, 2015) In the context of the Circus Maximus, this paper specifically analyzes how the structure has recovered from natural disaster.

3. Background of the Circus Maximus

The Circus Maximus is sited on the level ground of the Valley of Murcia, between Rome's Aventine and Palatine Hills. Originally constructed as a chariot racetrack in the 6th century BC, it once held the first and largest stadium in the Roman Empire. As the most suitable public space for grand religious processions, it also hosted these events between the 1st and 6th centuries AD. (Cartwright, 2013)

The Circus was originally made of wood (Figure 2) , having all wooden facilities, shops, and entrances. (Ames, 2016) The wooden seats and stands would frequently rot and require rebuilding. A fire in 31 AD completely destroyed most of the circus; “The Great Fire of Rome” in 64 AD not only burned down the circus but much of the rest of Rome, as well. The third fire in less than 200 years swept through the site in 80 AD. In 103 AD it was rebuilt in stone under the leadership of Trajan. (Grout, 1997) At its peak the Circus measured 2,307 feet long by 387 feet wide, with spectator capacities estimated up to 250,000. (Grout, 1997) The construction demonstrates several classic Roman sustainability techniques, such as building underground, reusing existing materials and repurposing the land.

Figure 2

Exploring the Circus Maximus personally, I noticed it to be a central location in Rome. The view of Palatine Hill is scenic and the space is walking distance from several residential areas. These factors make it ideal for a park location and being potentially being accessible to the city's population, although it’s surrounded by busy roads on all sides. Parking is hard to find around the Circus Maximus. I was surprised to see how little of the ancient structure is used today. The land is still relatively utilized, but the remains of the stadium are fenced off from the rest of the park as part of a ticketed museum. (Figures 3 and 4)
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Figure 3

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Figure 4

A modern image of the Circus Maximus park at sunset and the fenced museum entrance. Photos by author.

4. Represented Principles of Sustainability

4.1 Resiliency

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Figure 5

Rome Reimagine 2.jpg
Figure 6

An aerial view of the city center seen from the east, using recreation software to imagine the Circus Maximus over 2,000 years ago. Visible are the Tiber River, Circus Maximus, Palatine, and Colosseum.
The circus, the imperial palace on the adjacent Palatine Hill, and the Septizodium.
Retrieved from: http://romereborn.frischerconsulting.com/gallerycurrent.php#images_2_1

Rebuilding after natural disasters is an issue of concern for civil engineers as old as time. For as long as infrastructure has existed, Mother Nature has tested its sustainability. It today’s world with pressing natural disaster, the ability to respond is as important as ever. The Circus Maximus itself is an example of Roman disaster response, relief, and reconstruction.

Emperor Augustus (Figure 7) led the Circus Maximus’s first reconstruction after the fire in 31 AD also adding an imperial box on Palatine Hill. He also built an obelisk to decorate the median strip of the circus, known as the spina. The obelisk was dedicated to the Sun and was a monument of his conquest of Egypt. This obelisk is still standing today, displayed at the center of the Piazza del Popolo. (Circus Maximus, 2013) The second fire that impacted the Circus Maximus burned in “The Great Fire of Rome” in 64 AD. Tacitus said of the fire,“...it became so fierce and so rapid that it instantly seized in its grasp the entire length of the Circus.” (Squires, 2016) The fire occurred under Emperor Nero's (Figure 9) reign, but was rebuilt by Emperor Trajan. After another fire in 80 AD (Grout, 1997) it was Trajan (Figure 8) who restored the Circus to its maximum splendor.

Figure 7
Figure 7

Figure 8
Figure 8

Figure 9
Figure 9

A statue of Emperor Agustus, who led the first reconstruction.
A statue of Emperor Trajan, who restored the Circus Maximus to it's greatest ancient form.
A bust sculpture of Emperor Nero, who led the Empire during the greatest burning of Rome. Clearly he is upset he didn't get the memo to point to the top left corner.
Retrieved from: here.
Retrieved from: here.
Retrieved from: here.

After the fire, Emperor Nero imposed new building regulations specifically targeted to limit to height of buildings, restrict the use of wood as construction material, and the number of shared walls by adjoining structures. In order to replace timber use in buildings, fire-proof stone became the preferred alternative for construction material. To lessen congestion of tenements, courtyards and porticoes were incorporated into the architectural plans of residential housing. Roads were made wider to further lessen traffic congestion. Before 64 B.C. Roman pathways and roads typically accommodate the movement of a single cart, with few exceptions. Creating more open space and eliminating congestion meant that the population density of Rome would decline, and there would be fewer houses and tenements to accommodate the city's population of 1 million.

Nero paid to have rubble removed from Rome, using the material to fill the marshes on the coast near Ostia. This eliminated a valuable natural habitat for amphibians and birds. Nero encouraged owners of fire damaged Roman properties to sell their holdings and to purchase this newly made land created by the debris from the fire on the filled marshes and swamps. This was intended to be compensation for the owners. Nero planned to build a canal through this new “made land” that connected Ostia to Rome, but it never made it past the planning stage. The goal of building the canal to deliver harvested corn from Ostia to a healed Rome to feed the city’s population would have entailed significant ecological costs. A majority of the reconstruction after the city wide fire was funded by private investors who were rewarded with Roman citizenship. Nero himself was able to quickly rebuild the Circus Maximus amongst other public spaces by using his own imperial wealth, rather than imposing a tax on Rome’s fire weary inhabitants. (Penna and Rivers, 2013)

Learning from previous mistakes of flammable materials and determined to prevent further fire damage, Trajan build the stadium with all stone material. The Circus Maximus was built to be three stories high, becoming bigger, more impressive, and dramatic than ever before. The sitting area was built with marble. On the first story, there were arches and engaged columns that divided the seating into zones. There were specific seating areas reserved for Senators along the podium wall. Differing from the Colosseum and theater, the Circus Maximus was not segregated by gender. This provided opportunities for flirtation and dalliance, increasing Rome’s fondness toward the Circus’ and motivation to rebuild after disaster struck.

The Circus Maximus’ popularity was a big driving factor for its reconstruction. Even after both of its fires, it continued to be used until 549 AD. Because anyone could enter the stadium for free, it was a popular place to spend time. After its last race in 549 AD, the stadium started to become deserted. Some of it’s materials were stolen and used to construct new things in the area. The Circus’s decentralization led to it’s collapse. (Circus Maximus, 2013)

It is clear that Rome’s glory was reflected in its public spaces and buildings, such as the Circus Maximus. The massive reconstruction effort that the Emperors of Rome planned and paid for was intended to return the city to its wealth and status.

4.2 Social Sustainability

Social sustainability within engineering relates to how infrastructure can impact surrounding communities and societies, with results both positive and negative. Factors include how a building is used: seasonally or year-round? Open to the public, or restricted to specific membership? Employing local residents, or exporting local resources? The Circus Maximus affected a huge portion of ancient Rome’s population, across the full spectrum of social and economic status. It was a space where many could live and play, where families could watch brutal combat together or spectate a chariot race, where Romans could shop underground, find a potential suitor, or simply appreciate the beauty of the stadium. Here, we will explore the Circus Maximus’ social impact through time.

Over thousands of years, the Circus Maximus has been used for countless purposes. While many people think of sustainability as specifically relating to the environment, it is equally important to have a relevant use to the public. Being one of the most famous structures of the ancient world, the Circus Maximus was known for bringing spectators together to share an enjoyed event. Especially after facing turmoil of being burned down, the Romans truly had to care about the Circus in order to spend so much energy and resources toward its reconstruction. Dionysius of Halicarnassus described the Circus Maximus in 7 B.C. as “one of the most beautiful and admirable structures in Rome". (Hand, 2005) Although the seating in the Circus Maximus was organized by social class anyone could spectate events happening in the Circus. There were entrances strategically located in every shop of the circus so that thousands of people could enter and exit with inconvenience. (Hand, 2005) The Circus included latrines for the thousands of spectators that would spend days at the stadium watching events. They were state of the art toilets flushed with water from a nearby aqueduct. (sign at Circus Maximus)

Part of the Circus’ social sustainability lies under the Roman State’s determination to keep its population in line in times of political turmoil. By allowing Roman citizens from all classes to view gladiator battles, chariot races, and criminal executions, the State proved that in their eyes, human life was expendable. It instilled a sense of excitement and lust, as well as fear and devotion in its viewers. The Circus Maximus was a place where all Romans, regardless of class, were welcome. (Hand, 2005)

(Figure 10) Chariot races similar to those pictured in Ben Hur took place in the Circus Maximus.

Around the medieval times, the Circus was used for agriculture. It was full of fields, water mills, and vegetable gardens. (Squires, 2016) The small tower that stands at one end of the Circus Maximus hints to the fact that the area was predominantly an agricultural area, controlled by prominent medieval families. The tower, called the Tower of Moletta (Figure 11), is most likely built by the Frangipani family. They controlled parts of the Circus’ surrounding areas and a short-lived water mill they built during the 11th-12th century. The sourced streams that powered this mill started winding through the Palatine valley in the 6th or 7th century. The river had been channeled by Pope Callistus in 1122 to power the mill. Earlier in the medieval period, few arches and obelisks were still standing in the Circus Maximus. Most were moved to other locations around Rome by the 16th century. However, the relative emptiness of the circus was somewhat representative of its medieval realities. In addition to a few ruins from ancient Rome and the mill tower of the Frangipani, the circus had few dwellings along with farmland and open space. There were few buildings amongst the trees and agricultural land. (Brandt, 2015)

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(Figure 11) The Tower of Moletta standing in Rome in present day. Photo by author.

In the 19th century The Circus Maximus was an industrial zone, used by the “Anglo-Roman Society for Gas Lighting” to host a gasometer. The area was also packed with workshops and factories. (Squires, 2016) A gasworks park lived in the Circus Maximus during this age, but the park was cleared and excavated in the 1930’s. (Cartwright, 2013) From then on it became a park to resemble the shape of what once was the stadium, and now just a field.

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Figure 12

Concert Poster.jpg
Figure 13

Bruce poster.jpg
Figure 14

Posters adverting concerts hosted at the Circus Maximus.
Retrieved from: here.
Retrieved from: here.
Retrieved from: here.

In recent times, both the Rolling Stones and Bruce Springsteen have played at the Circus Maximus. The Rolling Stones concert received controversy both for it’s low offering price to rent the venue, and for potential damage that might incur from having a concert in such a historic place. (McKenna, 2014) When I visited the Circus Maximus, I wondered how concerts would be effectively held there. For the Rolling Stones concert, a temporary fence was built around the park in order to ticket fans inside. (Figure 15) A stage had to be built in order for the Rolling Stones to play there, but there didn’t appear to be a stage remaining anywhere on the property. Building a temporary 24 hour stage is a rather unsustainable use of materials. It seemed that having a concert would open up opportunity for graffiti and trash. “This office does not consider it appropriate to set aside Circus Maximus for the concert for which the risks of protecting archaeological heritage are not only elevated but also difficult to predict," said Maria Rosaria Barbera, in a cultural ministry document leaked to the media. (McKenna, 2014) Serious damage was done to the Circus as it hosted public celebrations for A.S. Roma's victory in the Italian football championship in 2006 and 2001. (Figure 16)

(Figure 15) A birds-eye view of the Rolling Stones concert in the Circus Maximus.

(Figure 16) Fans celebrate A.S. Roma's victory in the Circus Maximus.

Social sustainability is echoed throughout the history of the Circus Maximus. Although the stadium is not as popular as it was in ancient Rome, it is still used today. This shows sustainability throughout Roman society over the course of 2,800 years.

4.3 Environmental Sustainability

Environmental sustainability is the first area of sustainable infrastructure that most people think of. There are many reasons why reusing old buildings is important for the environment. The impacts of the extraction of old materials, transporting new materials, and the environmental impacts of processing construction are avoided. The Circus Maximus is a prime example of conserving land, having repurposed the same land many times over its lifespan. Continuing to use existing buildings on occupied land helps minimize the use of farms, forests, wildlife habitats and open space for new construction. Old buildings also embody the energy and carbon used to produce them. By recycling buildings, we prevent the further use of carbon from being released into the environment. Operating energy tend to be much less in old buildings. Because many ancient buildings were designed to take advantage of naturally occurring energy, they often consume less resources than newer buildings. From the Preservation Green Lab:

“Building owners, developers, policy makers, and green-building experts often assume that it is preferable to build a new, energy-efficient building than to retrofit an older building to the same level of efficiency” yet “… data from the U.S. Energy Information Administration (EIA) demonstrates that commercial buildings constructed before 1920 use less energy, per square foot, than buildings from any other decade of construction.” While this is not true for all older buildings, many old buildings are inherently green. (Mayes, 2014)

While environmental sustainability is a hot topic in the modern world, ancient Rome is littered with examples of architectural recycling. Virtually anywhere that Romans used marble and granite, recycling and reuse followed. Most of ancient Roman environmental recycling fell under one of two categories: adaptive reuse of immovable structures, when a building or monument is renovated and its primary function changes; and reuse of architectural elements, where both functional and decorative material is removed from one building to be incorporated in another. (Richards, 2017) The Circus Maximus in particular was an example of the latter.

Roman environmental sustainability is exhibited in much of its ancient infrastructure, such as the Pantheon. While the iconic and celebrated building was adapted for different religious uses throughout history, it has maintained its heritage while renovating its function. The Library of Celsus is another example. Destroyed by an earthquake and fire in 262 A.D., it’s materials were adapted into a public water fountain 100 years later. Romans were typical to opportunistically take advantage of natural disasters to salvage material. The process incorporated other recycled materials from nearby monuments, marble blocks and sculptures, which fits its change in function. This reuse of materials gave the non functional, yet historic, structure a new purpose and life. (Richards, 2017)

Recycling materials in Rome was also a form of political propaganda. Using past emperor’s pieces was an opportunity to rework the stone into the new emperor's own image. This bold inclusion of old material in a new monument led to a new architectural recycling technique that Romans became famous for. This trend became so popular that new laws were administered to protect public buildings from being stripped of their decoration. It was only if a building could not be restored, was it then permitted to recycle its materials. (Richards, 2017)

As I was observing the museum of the Circus Maximus, I interpreted it to be greener to save the materials already there than it would have been to create a new space on top of the field of land. It was fascinating to see the ancient leftover structures in the museum on site. This occupied less energy than it would have to move the old materials to a different part of Rome, into a separate museum. The park itself was pretty empty and seems to not be very well taken care of. Although this empty space is not currently using many resources, I believe the park could be much better utilized.

Much of the aspects of the Circus Maximus were restored or recycled, rather than completely rebuilt. This was concept was typical of Roman sustainability. In the Circus Maximus, the turning posts around the area that marked each lap were restored from older materials rather than originally built. (Grout, 1997) During Trajan’s reconstruction of the Circus Maximus after the fire of 64 A.D. the same land was used, rather than moving the stadium to a new part of Rome. Although a different location could have been chosen, it was significantly more environmentally sustainable to stay in the same place. Throughout its 2,800 year lifespan, the land it has occupied has been repurposed over and over. Even after the area was excavated and no longer used to host a stadium, land was used for agriculture and industrial purposes. The ancient river running near the Circus Maximus powered a mill and watered nearby crops. In modern times, the Circus Maximus still has a low environmental footprint. Although littered and graffitied, the park itself does very little to consume environmental resources.

4.3 a. Evidence of Neglect in The Circus Maximus

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napkin and pack of gum .jpg
Overgrown dirty grass.jpg

overgrown stairs.jpg
Cig trash gross.jpg
Cigarette pack trash in CM.jpg

sad soccer ball.jpg
trashy napkin ick.jpg

5. Summary and Conclusion

The Circus Maximus has a long and ancient history spanning over many generations of Roman entertainment.

  • Resilency: The Circus Maximus has been rebuilt over the course of three separate fires. Emperor Trajan who led its biggest reconstruction learned from the previous mistakes of the circus’s construction to create a more sustainable stadium.

  • Social Sustainability: The Circus’s history is much deeper than chariot races and gladiator battles. Although originally designed for classic Roman entertainment, it’s repurpose has spanned into agriculture, industrialism, museums, concert venue, and today serves as a public park.

  • Environmental Sustainability: Throughout the Circus’ reconstruction and repurposing, the environment has been kept in mind using techniques such as recycling older material and reusing the same land.

While visiting the Circus Maximus, I was initially confused and slightly disappointed. While there is a great history there, today the space is mostly a footprint of what once was. The space is relatively deserted, but has a lot of potential to be further utilized. An increase in shaded areas within the park would greatly improve its livability, especially in hot summer days. The lack of shade in the Circus Maximus provides little relief from the sun, especially in the heat of the main tourism season. The endless piles of trash and dirt also tend to drive people away. The city of Rome should hire caretakers to mow, water, clean, plant, and cater to the public space. Perhaps splat ball salesmen looking to turn their lives around. The lack of signage is in the park is confusing. It is only in the museum itself that any literature indicating that a stadium once stood there exists. An addition of signs with pictures of what life was like in the Circus Maximus 2,000 years ago as compared to today would increase public satisfaction with the space, while still leaving plenty of material for the museum. With the addition of shade, plants, a catered grassy area, and an increase in public signage, I believe the space could be significantly more utilized and welcoming. I would love to see the park used as more of a public community space. The area would be perfect for an addition of soccer fields, a place to hold movie screenings, holiday celebrations, to host a dog park, and much more.

Sustainability is as important a topic as ever before. When building, we have to keep future purposes that we can’t even know about yet in mind. As our world continues to grow, we can look to the Romans for sustainable lessons.

6. References

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McKenna, Josephine. “Rolling Stones Rome concert 'could damage Circus Maximus'.” The Telegraph, Telegraph Media Group, 16 Mar. 2014, www.telegraph.co.uk/news/worldnews/europe/italy/10701776/Rolling-Stones-Rome-concert-could-damage-Circus-Maximus.html.

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Squires, Nick. “Brothels, bars and betting shops - last surviving remnant of ancient Rome's Circus Maximus opened to the public after seven year restoration.” The Telegraph, Telegraph Media Group, 16 Nov. 2016, www.telegraph.co.uk/news/2016/11/16/brothels-bars-and-betting-shops---last-surviving-remnant-of-anci/.

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